Method and system for improving diffraction efficiency of acousto-optic tunable filter

Abstract

The invention relates to a method and a system for improving diffraction efficiency, in particular to a method and a system for improving the diffraction efficiency of an acousto-optic tunable filter, and solves the problems that the energy intensity of incident light from a target is reduced by half due to the fact that a front polarization device is additionally arranged in the prior art, then the diffraction efficiency of the acousto-optic tunable filter is reduced by half, and measurement is not facilitated under a weak light condition. The method is characterized by comprising the following steps of: 1, dividing natural light or non-polarized incident light from a target into transmission light and reflected light; 2, carrying out linear polarization treatment on the reflected light; then performing light path reversing, so that the light path direction is parallel to the light path direction of the transmission light obtained in the step 1; carrying out phase delay to enable the phase to be consistent with the phase of the transmission light obtained in the step 1; 3, combining the transmission light obtained in the step 1 with the reflected light after phase delay in the step 2; and 4, enabling the combined light and the ultrasonic waves to interact in the acousto-optic tunable filter, and outputting diffraction light.

Description

technical field [0001] The invention relates to a method and system for improving diffraction efficiency, in particular to a method and system for improving diffraction efficiency of an acousto-optic tunable filter. Background technique [0002] Acousto-optic tunable filter is a new type of light-splitting element in which ultrasonic waves and light waves can have acousto-optic interactions in anisotropic media. The acousto-optic tunable filter is mainly composed of an acousto-optic medium, a piezoelectric transducer, an absorber, and an ultrasonic frequency driver. The ultrasonic frequency driver emits an ultrasonic signal with a certain frequency, which is input into the acousto-optic medium through the piezoelectric transducer, and then forms an "ultrasonic grating" in the acousto-optic medium. When the incident light wave and the ultrasonic wave meet the momentum matching conditions, A nonlinear effect occurs in the acousto-optic medium to generate diffracted light wave...

AI Technical Summary

Problems solved by technology

[0014] The purpose of the present invention is to provide a method and system for improving the diffraction efficiency of the acousto-optic tunable filter, so as to solve the problem that the energy intensity of the natural light or non-polarized incident light from the target is reduced by half due to the addition of a pre-polarized device. Furthermore, the diffraction efficiency of the acousto-optic tunable filter is also reduced by half, which is very unfavorable for the technical problems of experimental measurement under weak light conditions.

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